Effects of public health interventions and zero COVID policy on paediatric diseases: A Southern China study

Background With the spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic in schools and communities, clinical evidence is needed to determine the impact of the pandemic and public health interventions under the zero coronavirus disease policy on the occurrence of common infectious diseases and non-infectious diseases among children. Methods The current study was designed to analyse the occurrence of common infectious diseases before and after the pandemic outbreak in southern China. Data was obtained for 1 801 728 patients admitted into children’s hospitals in Guangzhou between January 2017 and July 2022. Regression analysis was performed for data analysis. Results The annual occurrence of common paediatric infectious diseases remarkably decreased after the pandemic compared to the baseline before the pandemic and the monthly occurrence. Cases per month of common paediatric infectious diseases were significantly lower in five periods during the local outbreak when enhanced public health measures were in place. Cases of acute non-infectious diseases such as bone fractures were not reduced. Non-pharmaceutical interventions decreased annual and monthly cases of paediatric respiratory and intestinal infections during the coronavirus disease 2019 (COVID-19) pandemic, especially when enhanced public health interventions were in place. Conclusions Our findings provide clinical evidence that public health interventions under the dynamic zero COVID policy in the past three years had significant impacts on the occurrence of common respiratory and intestinal infectious diseases among children and adolescents but little impact on reducing non-infectious diseases such as leukaemia and bone fracture.


Online Supplementary Document
Table S1 STROBE checklist.

Table S2
The changes in average annual and monthly cases of common pediatric diseases before and after the COVID-19 pandemic.

Figure S1
The age distribution of included patients.

Figure S2
Disease distribution during the pandemic.

Figure S3
The case distribution of the identified pediatric diseases pre-COVID-19 pandemic (from 2017 to 2019).

Figure S4
The distribution of confirmed cases of COVID-19 in Guangzhou.

Figure S5
The case distribution for pediatric patients with leukemia.
Text S1 Study protocol.a Changes were calculated as the difference of the cases after the pandemic compared with the baseline before the pandemic.
b Data cut-off date was 31 July, 2022.

Figure S1
The age distribution for included patients.

Figure S2
The case distribution of identified diseases during the pandemic.

Figure S3
The case distribution of the identified pediatric diseases pre-COVID-19 pandemic (from 2017 to 2019).

Figure S4
The distribution of confirmed cases of COVID-19 in Guangzhou.

Figure S5
The case distribution for pediatric patients with leukemia.
Study data will be managed in compliance with local data management requirements for individual sites.Medical records of the subjects will be accessed by the site investigators for data collection.Clinical data will be extracted from the investigational site, including demographic data, annual and monthly cases of pediatric diseases identified by the inclusion criteria.

Source data and record archiving
Medical data of the subjects will be archived at the investigational site in compliance with local SOP.Studyrelative documents will be kept in the study files, and archived in a key-locked filing cabinet at the site.All essential documents will be retained at investigational sites for a of 5 years after the study has finished.

Data quality
The collected data will be cross-checked by two researchers for quality control, and analyzed by skilled staff with the supervision of a clinical physician and a specialist in epidemiology and hygenic statistics.

Ethics considerations 6.1 Local regulations/ ICH-GCP
The investigators ensure that the current study is conducted in accordance with the principles of the Declaration of Helsinki, ICH-GCP, and local regulations.

Informed consent
Informed consent is exempted by the IRB of the leading site since the data are exacted from the medical databases, which are de-identified before being collected for scientific research purposes to protect the privacy of patients.

Subject confidentiality
The study staff will safeguard the privacy of the subjects' personal data.The personal data will be de-identified before being collected.All documents will be stored securely and only accessible to study staff.

Independent Ethics Committees
The study protocol and informed consent form will be submitted by the investigators to the EC for written approval.The study procedure could be performed after the EC approval is available.
Cohort study-Give the eligibility criteria, and the sources and methods of selection of participants.Describe methods of follow- up Case-control study-Give the eligibility criteria, and the sources and methods of case ascertainment and control selection.Give the rationale for the choice of cases and controls Cross-sectional study-Give the eligibility criteria, and the sources and methods of selection of participants 6 (b) Cohort study-For matched studies, give matching criteria and number of exposed and unexposed *Give information separately for cases and controls in case-control studies and, if applicable, for exposed and unexposed groups in cohort and cross-sectional studies.Note: An Explanation and Elaboration article discusses each checklist item and gives methodological background and published examples of transparent reporting.The STROBE checklist is best used in conjunction with this article.Information on the STROBE Initiative is available at www.strobe-statement.org.Abbreviations: NA, not applicable.

Table S2
The changes in average annual and monthly cases of common pediatric diseases before and after the COVID-19 pandemic.
A descriptive statistic is employed to analyze the distribution features of variables.Categorical variables are presented as number and frequency rates.Fisher's exact test and χ 2 test are performed using SPSS software (version 26.0, IBM, Armonk, NY, USA) to compare the ratios among groups.Regression analysis is performed using Joinpoint software (version 4.8.0.1) with annual percent change (APC) as a key index to evaluate the trends of annual occurrence of leukemia from 2017 to 2021.Statistical significance is considered if p < 0.05.No imputation will be used for missing data.